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Sm-Nd年龄测定方法的新近应用,导致对许多太古宙变火成岩岩套已成功又合理地测定出火成岩结晶作用的精确时间。在火成岩处于亚固相蚀变和变质作用过程中,Sm和Nd似乎并未出现不稳定性状,而对这些岩石采用Rb-Sr法和Pb-Pb法测定年代往往是无效的。皮尔巴拉地块太古宙花岗岩-绿岩岩层的下部变质火山岩系(瓦拉沃纳 Warrawoona群)近来首次得出确实的年龄为34.52±16(2σ)Ma,它是由Pidgeon(1978)测定
The recent application of the Sm-Nd age determination method has led to the precise and successful determination of the igneous crystallization of many Archean altered igneous rocks. Sm and Nd do not appear to be unstable during igneous alteration and metamorphism of igneous rocks, but it is often ineffective to measure the ages of these rocks using Rb-Sr and Pb-Pb methods. The lower metamorphic volcanic series of the Archean granitic-greenstone strata of the Pilbara Massif (Warrawoona Group, Walla Walla) have for the first time recently produced a true age of 34.52 ± 16 (2σ) Ma as determined by Pidgeon (1978)